The present invention relates to new N-aryl and N-heteroarylurea derivatives, pharmaceutical compositions comprising such compounds, and the use of such compounds to inhibit intestinal absorption of cholesterol, lower serum cholesterol and reverse the development of atherosclerosis. The compounds are inhibitors of acyl coenzyme A: cholesterol acyltransferase (ACAT).
Cholesterol that is consumed in the diet (dietary cholesterol) is absorbed as free cholesterol by the mucosal cells of the small intestine. It is then esterified by the enzyme ACAT, packaged into particles known as chylomicrons, and released into the bloodstream. Chylomicrons are particles into which dietary cholesterol is packaged and transported in the bloodstream. By inhibiting the action of ACAT, the compounds of this invention prevent intestinal absorption of dietary cholesterol and thus lower serum cholesterol levels. They are therefore useful in preventing atherosclerosis, heart attacks and strokes.
By inhibiting the action of ACAT, the compounds of the present invention also enable cholesterol to be removed from the walls of blood vessels. This activity renders such compounds useful in slowing or reversing the development of atherosclerosis as well as in preventing heart attacks and strokes.
Other inhibitors of ACAT are referred to in U.S. Pat. Nos. 4,994,465, 4,716,175 and 4,743,605 (a divisional of the '175 patent) and in the European Patent Applications having publication numbers 0 242 610, 0 245 687, 0 252 524, 0 293 880, 0 297 610, 0 335 374, 0 335 375, 0 386 487, 0 399 422, 0 415 123, 0 421 456 and 0 439 059. Additional ACAT inhibitors are described in PCT publications WO 9015048 and WO 91/04027. Certain ureas and thioureas as antiatherosclerosis agents are referred to in U.S. Pat. No. 4,623,662.